keyword
MENU ▼
Read by QxMD icon Read
search

Stretching

keyword
https://www.readbyqxmd.com/read/29166112/charge-transfer-excited-states-seeking-a-balanced-and-efficient-wave-function-ansatz-in-variational-monte-carlo
#1
N S Blunt, Eric Neuscamman
We present a simple and efficient wave function ansatz for the treatment of excited charge-transfer states in real-space quantum Monte Carlo methods. Using the recently introduced variation-after-response method [E. Neuscamman, J. Chem. Phys. 145, 081103 (2016)], this ansatz allows a crucial orbital optimization step to be performed beyond a configuration interaction singles expansion, while only requiring calculation of two Slater determinant objects. We demonstrate this ansatz for the illustrative example of the stretched LiF molecule, for a range of excited states of formaldehyde, and finally for the more challenging ethylene-tetrafluoroethylene molecule...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166105/electrode-reactions-in-slowly-relaxing-media
#2
Dmitry V Matyushov, Marshall D Newton
Standard models of reaction kinetics in condensed materials rely on the Boltzmann-Gibbs distribution for the population of reactants at the top of the free energy barrier separating them from the products. While energy dissipation and quantum effects at the barrier top can potentially affect the transmission coefficient entering the rate pre-exponential factor, much stronger dynamical effects on the reaction barrier are caused by the breakdown of ergodicity for populating the reaction barrier (violation of the Boltzmann-Gibbs statistics)...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166091/string-like-collective-motion-and-diffusion-in-the-interfacial-region-of-ice
#3
Xinyi Wang, Xuhang Tong, Hao Zhang, Jack F Douglas
We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer...
November 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166062/nonadiabatic-photodissociation-dynamics-of-the-hydroxymethyl-radical-via-the-2-2-a-3s-rydberg-state-a-four-dimensional-quantum-study
#4
Changjian Xie, Christopher Malbon, David R Yarkony, Hua Guo
The quantum mechanical nonadiabatic photodissociation dynamics of the hydroxymethyl (CH2OH) radical in its lowest absorption band is investigated for the first time on a set of coupled diabatic potential energy surfaces determined by accurately fitting a large set of ab initio data. In this two-state approximation, only the ground and first excited states of CH2OH, which are coupled by conical intersections, are included. The reduced-dimensional dynamical model includes the CO stretch, the COH bend, the HCOH torsion, and the O-H dissociation coordinate...
June 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166058/structural-entanglements-in-protein-complexes
#5
Yani Zhao, Mateusz Chwastyk, Marek Cieplak
We consider multi-chain protein native structures and propose a criterion that determines whether two chains in the system are entangled or not. The criterion is based on the behavior observed by pulling at both termini of each chain simultaneously in the two chains. We have identified about 900 entangled systems in the Protein Data Bank and provided a more detailed analysis for several of them. We argue that entanglement enhances the thermodynamic stability of the system but it may have other functions: burying the hydrophobic residues at the interface and increasing the DNA or RNA binding area...
June 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29166047/ortho-para-interconversion-in-cation-water-complexes-the-case-of-v-h2o-and-nb-h2o-clusters
#6
T B Ward, E Miliordos, P D Carnegie, S S Xantheas, M A Duncan
Vanadium and niobium cation-water complexes, V(+)(H2O) and Nb(+)(H2O), are produced by laser vaporization in a pulsed supersonic expansion, mass selected in a time-of-flight spectrometer, and studied with infrared photodissociation spectroscopy using rare gas atom (Ar, Ne) complex predissociation. The vibrational bands measured in the O-H stretching region contain K-type rotational sub-band structure, which provides insight into the structures of these complexes. However, rotational sub-bands do not exhibit the simple patterns seen previously for other metal ion-water complexes...
June 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/29165847/breast-lesion-characterization-using-whole-lesion-histogram-analysis-with-stretched-exponential-diffusion-model
#7
Chunling Liu, Kun Wang, Xiaodan Li, Jine Zhang, Jie Ding, Karl Spuhler, Timothy Duong, Changhong Liang, Chuan Huang
BACKGROUND: Diffusion-weighted imaging (DWI) has been studied in breast imaging and can provide more information about diffusion, perfusion and other physiological interests than standard pulse sequences. The stretched-exponential model has previously been shown to be more reliable than conventional DWI techniques, but different diagnostic sensitivities were found from study to study. PURPOSE: This work investigated the characteristics of whole-lesion histogram parameters derived from the stretched-exponential diffusion model for benign and malignant breast lesions, compared them with conventional apparent diffusion coefficient (ADC), and further determined which histogram metrics can be best used to differentiate malignant from benign lesions...
November 22, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/29165142/the-effect-of-exercise-intensity-on-brain-derived-neurotrophic-factor-and-memory-in-adolescents
#8
Yong Kyun Jeon, Chang Ho Ha
BACKGROUND: Brain derived neurotrophic factor (BDNF) seems to serve as an important regulatory mechanism in the growth and development of neurons in many areas of the brain.Insulin-like growth factor 1 (IGF-1) is related to neurogenesis and regulation of the BDNF gene and is involved in the growth and differentiation of neurons.Cortisol is released in response to stimuli such as psychological oppression, anxiety, and fear. Stress also induces changes in BDNF. The purpose of this study was thus to examine the effects of varying intensities of aerobic exercise on resting serum BDNF, IGF-1 concentrations, cortisol, and memory of adolescents...
April 4, 2017: Environmental Health and Preventive Medicine
https://www.readbyqxmd.com/read/29165129/comparative-study-on-three-different-methods-for-arm-span-measurement-the-japan-environment-and-children-s-study-pilot
#9
Mayumi Tsuji, Tadayuki Ayabe, Rie Tanaka, Ayako Senju, Eiji Shibata, Shunsuke Araki, Seiichi Morokuma, Masafumi Sanefuji, Koichi Kusuhara, Toshihiro Kawamoto
BACKGROUND: Arm span is an important measure for the assessment of growth and hormone deficiency diseases. In an epidemiological survey, with a large number of subjects' indicators, it is especially valuable to establish methods which can measure both quickly and accurately. However, there are various methods, and the length of arm span may vary according to the medical institution. METHODS: The arm span of nine 6-year old subjects was measured using two institutional standard methods, A and B, and a third method C which is an improved method and has been used for the first time in this study...
April 4, 2017: Environmental Health and Preventive Medicine
https://www.readbyqxmd.com/read/29164881/monitoring-local-strain-vector-in-atomic-layered-mose2-by-second-harmonic-generation
#10
Jing Liang, Jin Zhang, Zhenzhu Li, Hao Hong, Jinhuan Wang, Zhihong Zhang, Xu Zhou, Ruixi Qiao, Jiyu Xu, Peng Gao, Zhirong Liu, Zhongfan Liu, Zhipei Sun, Sheng Meng, Kaihui Liu, Dapeng Yu
Strain serves as a powerful freedom to effectively, reversibly, and continuously engineer the physical and chemical properties of two-dimensional (2D) materials, such as bandgap, phase diagram, and reaction activity. Although there is a high demand for full characterization of the strain vector at local points, it is still very challenging to measure the local strain amplitude and its direction. Here, we report a novel approach to monitor the local strain vector in 2D molybdenum diselenide (MoSe2) by polarization-dependent optical second-harmonic generation (SHG)...
November 22, 2017: Nano Letters
https://www.readbyqxmd.com/read/29163203/cyclic-stretch-alters-vascular-reactivity-of-mouse-aortic-segments
#11
Arthur Leloup, Sofie De Moudt, Cor Van Hove, Paul Fransen
Large, elastic arteries buffer the pressure wave originating in the left ventricle and are constantly exposed to higher amplitudes of cyclic stretch (10%) than muscular arteries (2%). As a crucial factor for endothelial and smooth muscle cell function, cyclic stretch has, however, never been studied in ex vivo aortic segments of mice. To investigate the effects of cyclic stretch on vaso-reactivity of mouse aortic segments, we used the Rodent Oscillatory Tension Set-up to study Arterial Compliance (ROTSAC). The aortic segments were clamped at frequencies of 6-600 bpm between two variable preloads, thereby mimicking dilation as upon left ventricular systole and recoiling as during diastole...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29162803/mdia1-senses-both-force-and-torque-during-f-actin-filament-polymerization
#12
Miao Yu, Xin Yuan, Chen Lu, Shimin Le, Ryo Kawamura, Artem K Efremov, Zhihai Zhao, Michael M Kozlov, Michael Sheetz, Alexander Bershadsky, Jie Yan
Formins, an important family of force-bearing actin-polymerizing factors, function as homodimers that bind with the barbed end of actin filaments through a ring-like structure assembled from dimerized FH2 domains. It has been hypothesized that force applied to formin may facilitate transition of the FH2 ring from an inhibitory closed conformation to a permissive open conformation, speeding up actin polymerization. We confirm this hypothesis for mDia1 dependent actin polymerization by stretching a single-actin filament in the absence of profilin using magnetic tweezers, and observe that increasing force from 0...
November 21, 2017: Nature Communications
https://www.readbyqxmd.com/read/29162778/ryanodine-receptor-type-2-plays-a-role-in-the-development-of-cardiac-fibrosis-under-mechanical-stretch-through-tgf%C3%AE-1
#13
Zhiwen Ding, Jie Yuan, Yanyan Liang, Jian Wu, Hui Gong, Yong Ye, Guoliang Jiang, Peipei Yin, Yang Li, Guoping Zhang, Chunjie Yang, Junjie Guo, Zhidan Chen, Xingxu Wang, Liqing Weng, Yunzeng Zou
Ryanodine receptor type 2 (RyR-2), the main Ca(2+) release channel from sarcoplasmic reticulum in cardiomyocytes, plays a vital role in the regulation ofmyocardial contractile function and cardiac hypertrophy. However, the role of RyR-2 in cardiac fibrosis during the development of cardiac hypertrophy remains unclear.In this study, we examined whether RyR-2 regulates TGFβ1, which is secreted from cardiomyocytes and exerts on cardiac fibrosis using cultured cardiomyocytes and cardiac fibroblasts of neonatal rats...
November 22, 2017: International Heart Journal
https://www.readbyqxmd.com/read/29161622/on-denny-brown-s-spastic-dystonia-what-is-it-and-what-causes-it
#14
REVIEW
Jakob Lorentzen, Maud Pradines, Jean-Michel Gracies, Jens Bo Nielsen
In this review, we will work around two simple definitions of two different entities, which most often co-exist in patients with lesions to central motor pathways: Spasticity is "Enhanced excitability of velocity-dependent responses to phasic stretch at rest", which will not be the subject of this review, while Spastic dystonia is tonic, chronic, involuntary muscle contraction in the absence of any stretch or any voluntary command (Gracies, 2005). Spastic dystonia is a much less well understood entity that will be the subject this review...
November 4, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/29159996/demographic-characteristics-of-teenage-boys-with-horizontal-striae-distensae-of-the-lower-back
#15
Emily Boozalis, Anna L Grossberg, Katherine B Puttgen, Candrice R Heath, Bernard A Cohen
BACKGROUND: This study examines the clinical characteristics and demographics of teenage boys with horizontal striae distensae of the lower back in an outpatient setting. METHODS: Retrospective medical chart reviews and telephone survey studies were completed on an outpatient cohort of 12 boys 11 to 17 years of age with a clinical diagnosis of transverse striae distensae of the lower back at a single-center, university-based, pediatric dermatology practice. We evaluated the clinical features of the striae, participant demographic characteristics, and past medical history...
November 21, 2017: Pediatric Dermatology
https://www.readbyqxmd.com/read/29159321/lie-group-analysis-of-magnetohydrodynamic-tangent-hyperbolic-fluid-flow-towards-a-stretching-sheet-with-slip-conditions
#16
Zakir Ullah, Gul Zaman
In this paper, we studied MHD two dimensional flow of an incompressible tangent hyperbolic fluid flow and heat transfer towards a stretching sheet with velocity and thermal slip. Lie group analysis is used to develop new similarity transformation, using these similarity transformation the governing nonlinear partial differential equation are reduced into a system of coupled nonlinear ordinary differential equation. The obtained system is solved numerically by applying shooting method. Effects of pertinent parameters on the velocity and temperature profiles, skin friction, local Nusselt number are graphically presented and discussed...
November 2017: Heliyon
https://www.readbyqxmd.com/read/29158288/time-dependent-testing-evaluation-and-modeling-for-rubber-stopper-seal-performance
#17
Qingyu Zeng, Xia Zhao
Sufficient rubber stopper sealing performance throughout the entire sealed product life cycle is essential for maintaining container closure integrity (CCI) in the parenteral packaging industry. However, prior publications have lacked systematic considerations for the time-dependent influence on sealing performance that results from the viscoelastic characteristics of the rubber stoppers. In this paper, we report results of an effort to study these effects, by applying both compression stress relaxation (CSR) testing and residual seal force (RSF) testing for time-dependent experimental data collection...
November 20, 2017: PDA Journal of Pharmaceutical Science and Technology
https://www.readbyqxmd.com/read/29157833/vasodilatory-effect-of-asafoetida-essential-oil-on-rat-aorta-rings-the-role-of-nitric-oxide-prostacyclin-and-calcium-channels
#18
Hassan Esmaeili, Mozhdeh Sharifi, Mansour Esmailidehaj, Mohammad Ebrahim Rezvani, Zeynab Hafizibarjin
BACKGROUND: Asafoetida is an oleo-gum resin mainly obtained from Ferula assa-foetida L. species in the apiaceae family. Previous studies have shown that it has antispasmodic effects on rat's and pig's ileums. PURPOSE: The main goals of this study were to assess the vasodilatory effect of asafoetida essential oil (AEO) on the contractile response of rat's aorta rings and to find the role of nitric oxide, cyclooxygenase, and calcium channels. Thoracic aorta rings were stretched under a steady-state tension of 1 g in an organ bath apparatus for 1 h and then precontracted by KCl (80 mM) in the presence and absence of AEO...
December 1, 2017: Phytomedicine: International Journal of Phytotherapy and Phytopharmacology
https://www.readbyqxmd.com/read/29156620/stretchable-highly-durable-ternary-nanocomposite-strain-sensor-for-structural-health-monitoring-of-flexible-aircraft
#19
Feng Yin, Dong Ye, Chen Zhu, Lei Qiu, YongAn Huang
Harmonious developments of electrical and mechanical performances are crucial for stretchable sensors in structural health monitoring (SHM) of flexible aircraft such as aerostats and morphing aircrafts. In this study, we prepared a highly durable ternary conductive nanocomposite made of polydimethylsiloxane (PDMS), carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) to fabricate stretchable strain sensors. The nanocomposite has excellent electrical and mechanical properties by intensively optimizing the weight percentage of conducting fillers as well as the ratio of PDMS pre-polymer and curing agent...
November 20, 2017: Sensors
https://www.readbyqxmd.com/read/29156124/definition-of-free-o-h-groups-of-water-at-the-air-water-interface
#20
Fujie Tang, Tatsuhiko Ohto, Taisuke Hasegawa, Wen Jun Xie, Limei Xu, Mischa Bonn, Yuki Nagata
Free O-H groups of water are often found at the water-hydrophobic medium interface, e.g. for water contact with hydrophobic protein residues, or at the water-air interface. In surface-specific vibrational spectroscopic studies using sum-frequency generation (SFG) spectroscopy, free O-H groups are experimentally well characterized in the O-H stretch region by a sharp 3700 cm(-1) peak. Although these free O-H groups are often defined as the O-H groups which are not hydrogen-bonded to other water molecules, a direct correlation between such non-hydrogen-bonded O-H group and the 3700 cm(-1) SFG response has been lacking...
November 20, 2017: Journal of Chemical Theory and Computation
keyword
keyword
28319
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"